Machine for treating metallic sheets



'A Oct. 24, 1939. C, s, WOOLFORD '2,176,939

MACHINE FOR TREATING METALLIC SHEETS Filed April ll, 1935 4 Sheets-Sheet l www ww www.. E

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MACHINE FOR TREATING METALLIC SHEETS Filed April ll, 1935 4 Sheets-Sheet 2 d l-\ V Q Q s A QE oct. 24, 1939. C. s. WQOLFRD. 2,176,939

MACHINE FOR TREATING METALLIC SHEETS INVENTO Oct. 24, 1939.

C. S. WOOLFORD MACHINE FOR TREATING METALLIC SHEETS Filed April 11, 1955 4 Sheets-Sheet 4 Patented Oct. 24, 1939 UNITED STATES 14 Claims.

, The present invention relates to a machine for treating metallic sheets so that portions may be united with other portions of the same or with other sheets and has particular reference to devices for cleaning and abrading marginal surfaces of sheet material such as container body blanks, the edges of which are to be secured to gether as by soldering, welding, brazing or the like.

An object of the invention is the provision of a machine for abrading portions of metallic sheets such as container body blanks wherein marginal surfaces of the blank are mechanically cleaned and scoured to present a surface of virunited in a subsequent operation.

Another object is the provision of such a sheet cleaning machinewherein the sheets are moved continuously along Aa path of travel passing through a plurality of cleaning stations having abrade the top and bottom marginal surfaces y along opposing edges as the sheets pass by, after which the sheets are delivered into a magazine and automatically arranged in stack formation. Still another object is the provision of a machine of the character described wherein the edges to be cleaned are moved vertically into engagement with the cleaning elements as the sheets pass through the stations, the forward movement of the sheet as it approaches a cleaning element results in actuation of detecting devices Which delay the vertical movement of the edges until the forward corners of the sheet are well under the cleaning element so as to prevent utilation of the same.

A further object is the provision in such a surface cleaning machine of control devices which overn the rotations of the cleaning elements so that'their rotations are periodically reversed to l prevent wearing away of the element in one diection, the reversal being effected automatically when a predetermined number of sheets have een cleaned. Numerous other objects and Aadvantages of the invention will be apparent as it is better understood from the following description, which, taken in connection with the accompanying rawings, discloses a preferred embodiment hereof.

Referring to the drawings:

Figure 1 is a side elevation of a machine in hich the instant invention is embodied, parts eing broken away; y,

gin metal so that such surfaces may be eiectively.

rotating cleaning elements which successively PATENT OFFICE `2,178,939 MACHINE FOR TREATING METALLIC SHEETS Custis S. Woolford, South Orange, N. J., assignor to American Can Company, New York,I N. Y., a corporation of New Jersey Application April 11, 1935, Serial No. 15,862

Fig. 2 is a top plan view of the machine. with parts broken away;

Fig.` 3 is an enlarged transverse section taken substantially along the vertical line 3 3 in Fig. 1, parts being broken away; 5

Fig. 4 is a fragmentary detail section of certain of the parts illustrated in Fig. 3 but showing these parts in a different position;

Fig. 5 is an enlarged vfragmentary detailed plan view taken substantially along the horizontal line 10 5-5 in Fig. 3;

Fig. 6 is an enlarged transverse section taken substantially along the vertical line 6--6 in Fig. 1, and having parts broken away; and

Fig. 'I is a wiring diagram of the electric con- `15 trols associated with the machine.

In the illustrated and preferred embodiment of the invention, sheets or blanks a are horizontally positioned, by any suitable means, on a conveyor which carries them through cleaning-2p stations A and B. These stations have associated continuously rotating cleaning elements for scouring or abrading marginal surfaces of a blank along opposite sides and on top and bottom.

'I'he blanks, in passing through the stations, g5 engage trip levers which, when moved, release spring held instrumentalities which. press the opposed margins of the blank into engagement with the cleaning elements. At the station A the marginal side edges of the blank are pressed up .2. and its top marginal surfaces are cleaned. At the station B the sides of the blank are depressed and its bottom marginal surfaces are cleaned.

Thus both top and bottom marginal surfaces along the side edges of each blank are cleaned or abraded to expose. the virgin metal, 'Ihis cleaning action provides surfaces free from any foreign matter and these surfaces are then in proper condition for uniting by a subsequent soldering, welding, brazing or the like operation.

.After passing Ithe stations A, B the blanks are carried to the end of the conveyor and there transferred into an inclinedK chute. The blanks slide down the chute by gravity, passing over anl air blast opening which at the proper time directs a jet of air against the bottom surface of the blank. This sets the blank up on its front edge and while still in this position it continues to slide down the chute until it comes to rest in stack formation at the bottom of the chute. 'The 50 shape and position of the chute permits easy re- .moval therefrom lof the cleaned sheets. Y

The sheets or blanks a (Figs. 1 and 2) are carried through the machine for the cleaning operation on a pair of spacedand parallel endless chain 65 I1. A collar conveyors I I. 'Ihese conveyors are provided with spaced feed dogs I 2 which engage behind the blanks and hold them in proper position while they are being carried forward. Other spaced stop dogs I3 also provided on the conveyors are positioned in front of the blanks to prevent their longitudinal displacement during the cleaning operation.

The conveyors II extend the full length of the machine and move between a pair of spaced, parallel side frames I5. These frames are tied together at each end by integral web sections I1, I 9, which are formed into legs by which the entire machine may be supported.

At the blank inserting or feed end of the machine (to the left as viewed lin Fig. 1) the conveyor chains I I take over spaced idler sprockets 2l which are pinned to a cross shaft 22 journaled in bearings 23 formed in the side frames I5 At the opposite or discharge end of the machine the conveyor chains take over similarly spaced drive sprockets 25 which are mounted on a horizontal sprocket shaft 26 journaled in bearings 21 formed in the side frames I5.

In this manner the upper runs of the conveyor chains move horizontally and just below the top surface of the side frames. These side frames serve as guides for the blanks as the latter are carried along between them.

The sprocket shaft 26 is driven through a sprocket 28 (Fig. 2) which is mounted on an end of the sprocket shaft where it projects beyond one of the frames I5. This sprocket 28 is actuated by a chain 29 carried on a drive sprocket 32 which is mounted on an end of a driven shaft 33. Shaft 33 is journaled in suitable bearings formed in a bracket 35 which is bolted to the web member I9.

Shaft 33 also carries a bevel gear 36 (Fig. 1) which meshes with a similar gear 31 mounted on one end of a longitudinal cam shaft 38. The cam shaft is carried in a bearing 4I formed in the web member I9 and in a bearing 4 2 formed in the opposite web member I1. A collar 43 pinned on the shaft adjacent the bearing 42 prevents longitudinal displacement thereof.

The cam shaft 38 is continuously rotated from a suitable source of power such las an electric motor 45. For this purpose the cam shaft carries a spur gear 46 which meshes with a pinion 41 mounted on a short shaft 48 which is secured in a boss 49 formed on the web member 5I pinned yto the opposite end of the shaft prevents displacement of the pinion.

The pinion 41 is formed as an integral part of a gear 52 which meshes with a main driving pinion 53 mounted on the motor shaft. 'I'hus continuous rotation of the motor is transmitted through this gear train to the cam shaft which in turn actuates the driven cross shaft 33 and its A sprocket to drive the conveyors II.

A blank a as it is being carried forward on the conveyor chains II first passes through the cleaning station A. This station contains a set of four cleaning elements or brushes disposed in pairs on each side of the machine, each pair being located above or below the path of travel of the side marginal edges of the moving blank (Figs. 1, 2 and 3).

Each brush comprises a plurality of vertically disposed hardened steel wires 55 (see also Fig. which at their upper ends are set in a ring 58. 'I'he ring in turn is loosely mounted on a cylindrical mandrel 51 the upper end of which 1s re-4 duced in diameter and rotatably carried in a bearing 59.

Bearing 59 is formed on a bracket 6I which is bolted to the top of a table 62 which extends laterally from the side of the frame I5 and is formed integrally therewith. There are two of these brackets 6I at station A, one on each side of the machine and similarly there are two tables 62, one on each side.

'I'he brush wires 55 are held compactly in place around the mandrel 51 by an encircling tubular shell 64. The upper end of the shell engages over an enlarged head 65 of the mandrel and is drawn tightly against a shoulder 66 by a collar 61, which fits over the top of the shoulder and threadedly engages the top of the shell.

'I'he bottom cleaning end of each wire brush 55 extends down below the bottom edge of the shell 64 and the mandrel 51 and parts carried thereby may be adjusted up or down to properly position the brush to engage the surface of the blank to be cleaned. For this purpose the brush ring 56 is connected by a horizontal pin 1I to a central vertical rod 12 disposed in a vertical bore 13 formed in the mandrel 51. The pin 1I is carried in the lower end of the rod and extends transversely on both sides passing through an elongated slot 14 formed in the mandrel. 'I'he ends of the pin are secured in suitable bores formed in the ring 56.

The upper end of the rod 12 is reduced in diameter and extends through a tubular bushing 16 which threadedly engages within the upper part of the mandrel bore 13. A collar 11 pinned to the top end of the rod, holds the latter in the bushing. Manual turning of the bushing within its threaded seat adjusts the brush into the desired vertical position. This position is then maintained by a lock nut 18 which threadedly engages the bushing and which is screwed down against the top of the mandrel. Y

Each of the pair of brushes on a side is rapidly rotated but in opposite directions and each front or rear brush rotates in a different direction to the corresponding brush on the opposite side of the machine. This is effected by a gear train on each side of station A which connects the pair of brushes on that side with an independent source of power, preferably an electric motor.

For this purpose the reduced upper end of each brush mandrel 51 extends above its bearing 59 and is keyed to a gear 8| (Figs. 2 and 3). These gears mesh with a pair of intermediate idler gears 82 mounted on short shouldered studs 83 which are riveted in place in bosses 80 formed on the bracket 8|.

One of the idler gears meshes with a driving gear 84 mounted on the end of a vertical shaft 85 journaled in a bearing 88 formed on the bracket 6I. Shaft 85 may be the motor shaft of a continuously rotating electric motor 81 which is bolted to the table 62 adjacent the bracket 6I. There are therefore two of these motors at station A one for each side of the machine.

As a blank a passes through the station A its side edges are lifted into engagement with the rotating brushes. During this passage the blank is held against vertical displacement along its` center by a pressure bar 9| which extends across and through both stations A and'B (Figs. 1, 2 and 3). The bar is thus disposed longitudinally of the machine and is hung in place and supported at its ends on transverse plates 92 which are in turn secured to thetop edges of the side frames I5. f

The moving blank successively engages the first and second pair of brushes 55 at station A thus completing the cleaning operation on its upper surface in two stages. At each of these stages of cleaning the blank is lifted by instrumentalities which will now be described, the construction and operation for each brush being identical and hence a description of only one of these sets being sufcient.

A pair of bell cranks 93 (Figs. 1, 2 and 3) are disposed on each side of the machine one under each of the brushes 55. Each crank is mounted on a short shaft 94 which is carried in bearings 95 formed in a bracket 90 which may be an integral part of the side frame I5. Each bell crank is provided with a substantially horizontal leg 90 which extends under the side edge of the blank when the latter is passing through the station terminating in an elongated pad 99. It is this pad 99 that engages under the edge of the blank and lifts it into contact with the brush.

Each bell crank is also provided with a substantially vertical, depending leg IOI. The lower end of this leg is engaged by one end of a coiled spring |02 and the other end of the spring is secured into aneye bolt |09 which in turn is threadedly seated in the side of the frame I5. It is these springs which under certain conditions pivot the cranks on their shafts and cause the pads 99 to lift the blank into cleaning engagement with the brushes.

The bell cranks 99 are held depressed until a blank a is presented for cleaning, the release of the cranks being effected during the forward movement of the blank by the latter releasing certain holding elements. These elements comprise latch arms |05 and one end of each arm engages against and holds back its associated bell crank leg IOI when the holding elements retain the bell cranks depressed (Fig. 3).

Each arm |05 is held in leg engaging position by a spring |01 (Figs. 1 and 2). One end of the spring engages a depending lug |00 which is formed as an integral part of the arm while the other end is hooked in an eye |09 secured in the side of the adjacent frame '|5.

Each latch arm |05 is mounted at the end of one or the other of a pair of horizontal cross .shafts III carried in bearings I|2 formed in the side frames I5. Each shaft is disposed under the upper run of the conveyor chains I I and carries a trip finger II3 which extends forward and longitudinally of the pressure bar 9|. The free end of the finger when not engaged by a blank extends upv into the path of travel of the blank and into a clearance slot I Il formed in the pressure bar.

Thus a blank a moving toward the brushes at station A engages first one and then the other of the trip fingers and rocks the associated shaft and the two latch arms thereon. This is done against the resistance of the spring |01. The forward ends of the arms are thus lowered and move adjacent a notch or set back IIO (Fig. 3) formed in the leg IOI of each bell crank 90 and this unlatches or releases the associated bell cranks.

The lifting of the blank, however, is delayed until its front edge is well under the brush. This is done to prevent the forward corners of the blank from being mutilated or damaged by the brushes. When released from the holding latch, a crank 991s held back by a cam actuated auxiliary bell crank |I5 (Fig. 3). 4

The auxiliary bell crank is mounted on a pin I|5 carried in lugs II'I formed on the side of the frame I5. The upper end of a substantially vertical leg II8 of the crank is in the path of a setscrew II9 carried in the lower end of the bell crank leg I 0I when the latch arm |05 is moved opposite the notch IIO. 'I'his setscrew therefore engages the leg IIB and the bell crank 90 is prevented from further movement.

Another leg I2I of the auxiliary bell crank extends through an opening |22 formed in the side of the frame I5 and carries a cam roller |23. Roller |23 operates with an edge cam |24 which is mounted on the cam shaft 30 and in the position shown in Fig. 3 the cam is on its high point and holding the leg I I0 in its outer position. Engagement between roller and cam of each auxiliary bell crank II5 is maintained by a spring |25 having one end hooked into an aperture |25 formed in the auxiliary crank leg IIO and the other end in an eye bolt |21 secured in the side of the frame I5. A

When the front edge of the blank is fully un- A der the brushes the cams |24 move to low point abrades its upper marginal surfaces `vas illustrated f in 5. The high speed of rotation of the' brushes and the constant changing of the engaged surfaces as brought about by the advance- .ment of the blank is very effective. In addition the two stage or double cleaning action insures full abrasion of the surface down to the virgin metal.

Constant rotation of the brushes in one direction while cleaning the blanks gradually wears the ends of the wires flat or at a slight angle and to lengthen the life of their effective cleaning action provision is made for automatically reversing the direction of rotation of all the brushes simultaneously after a predetermined number of blanks have been cleaned. 'I'his action causes the wires of the brush to slightly flex in the opposite direction and to present the sharp angular portion of the face of the wire to the blank surface instead of the fiat worn edge. This in its eil'ect is equivalent to renewing the abrading action of the wires. p

-The electric motors which drive the brushes are of the reversible type and are controlled by reversing devices. These devices are electrically associated with the power circuits which are schematically illustrated in the wiring diagram in Fig. 7 and will be fully explained in connection with a subsequent detailed description of that figure. v

After the cleaning operation at station A, continued forward movement `of the conveyors II carries the blank through station B. While passing through this latter station its lower marginal surfaces are subjected to the same kind of a cleaning operation. Station B is also provided with a set of four cylindrical wire brushes designated by theo numeral I4I (Figs. 2 and 6) which are similar in construction to the brushes 55 and which are also'arranged in pairs. The brushes III are located below the upper run of vthe conveyor and are in an inverted position A being disposed in openings |42 formed in the side frames I5.

Each brush is supported on the lower end of a mandrel |43 which extends up above the brush in a reduced diameter which is journaled in a stationary bearing |44. Bearing |44 is formed in a bracket |45 which is bolted to the top of a table 148 extending laterally from the outer side of the frame I5. There are two of these brackets 145 and two tables |46. one for each side of the machine and supporting the brushes and associated parts located on that side.

'I'he wires of each brush are held in compact cylindrical form by an encircling tubular shell |41 corresponding to the shell 64 of the brushes 55. The lower end of the shell is mounted on a lower shouldered part |48 of the mandrel |43 and is locked in position by a nut |49 threadedly engaged therewith. 'I'he brush is connected to a centrally disposed vertical'rod |52 by a. horizontal cross pin |53 which passes through the lower end of the rod and through a vertical slot |54 formed in the mandrel. The ends of the pin are engaged in a ring |55 this being a ring in which the brush wires are embedded.

The rod |52 is adjustably carried in a central bore |51 formed in the mandrel and at its upper end the rod is shouldered similar to the rod 12. This shouldered end of rod 52 extends beyond the mandrel |63 and through an adjusting sleeve |58 which is threadedly engaged in the upper end of the bore |51. A collar |59 secured to the rod holds the sleeve in position. By turning the sleeve, the rod and hence the brush may be adjusted vertically. When adjusted the parts are held by a lock nut ISI which threadedly engages the sleeve and clamps on the upper end of the mandrel.

Like the brushes 55, the brushes I 4| are continuously rotated at high speed. This is eiected by driving units identical in construction with 'the devices used in connection with the brushes at station A. Each mandrel 43 carries at its upper end a gear |65. The two gears on each side of the machine mesh with a pair of intermeshing gears |68 mounted on shouldered studs i'i secured in 'bosses |58 formed on the brackets |451 One of the gears |86, on each side oi the machine, meshes with a driving gear |59 carried on one end of a shaft Hi journaled in a bearing i12 formed in the bracket |45. The shaft iii is the main drive shaft of an electric motor i118 which is mounted on the table MS adjacent the bracket.

There are two oflthese motors, one for each side of the machine, and there is in this manner an independent drive for each set of brushes on a side. Like the motors associated with the station A, the motors E13 are of the reversible type and are controlled electrically by the same devices and for the same purpose. This will be hereinafter explained in connection with Fig. '1.

In station B the lower side marginal surfaces 'of the moving blank a are depressed into engagement with the rotating brushes l di for the cleaning operation. This cleaning is effected in two stages as at the station A, each stage utilizing a separate transverse pair of brushes. The depressing instrumentalities for each stage are in duplicate and are identical in construction and operation hence only one of the sets will be described.

Depression of the sideE edges of the blank is effected by bell cranks |15 (Figs. i, 2 and 6) there being two of these on each side of the machine under the pressure bar 9|,

above the brushes |4I. The bell cranks are mounted on short shafts |16 carried in bearings |11 formed in brackets |18 which may be an integral part of the frames l5. Each crank has a substantially horizontal leg IBI which terminates at its outer end in an elongated pad |82 which engages the side edge of the blank when it is pressed into engagement with the brush.

Actuation of each crank so that its pad engages the blank is effected by a spring |83. One end of the spring is hooked over a depending leg |84 of the crank and the other end is hooked over a lug |85 depending from the bottom of the table |46. The cranks |15 are held in raised position until a blank is passed into the station for cleaning. This is effected by latch arms |81 of holding elements one end of each latch arm providing an interference for its associated crank leg |84.

'Ihe latch arm is held in this stop position by a coil spring |89 having one end engaged in a lug I 9| (Fig. 1) formed as an integral part of the arm. The other end of the spring is hooked over a pin |92 secured in the frames I5.

The latch arms |81 are mounted on the ends of one of two horizontal cross-shafts |95 carried in bearings |96 formed in the side frames l5. Intermediate the bearings and disposed directly each shaft carries a trip finger |91 (Fig. 6) which normally projects up and into a slot |98 cut through the bar. As at the station A there is one of these lingers for each stage of cleaning.

These ngers are successively engaged by the forward edge of the advancing blank coming into 1 the station and when so tripped the latch arms are shifted to a position alongside of a notched or recessed part |99 of the leg |84. The bell cranks |15 are thus freed from the action of the latch arms or -holding elements. Movement of the associated bell crank, however, is delayed `until the forward edge of the blank is well over the top of the brush at that position. This is to prevent the forward corners of the blank being mutilated or damaged by the brushes.

This delayed action is brought about by can actuated auxiliary bell cranks 20| (Fig. 6) mounted on short shafts 202 which are carried in lugs 293 orined in the frames i5. One leg of each auxiliary bell crank is indicated by the reference character 205 and this leg carries a setscrew 20E at its upper end. The other leg, indicated by the reference character 201, extends through an opening 208 formed in the frame l and carries at its end a cam roller 209.

Cam roller 209 engages with an edge cam iii carried on the cam shaft 38 the roller being kept in engagement with the cam by a coiled compression spring 52H3. This spring is seated at 2H in the frame i5 and its outer end engages against a pad 2I5 formed on the auxiliary bell crank leg 205.

The cam is rotated in time with the travel of the blank on the conveyor and thus when the front edge of a blank is properly located over the top of a set of brushes, either at the rst or second stage, the cams 2|| move the auxiliary cranks 20| and carry the setscrews back and out of holding position. This fully releases the bell cranks |75 which are thereupon moved by the springs |83 and this brings the bell crank pads |82 into blank engaging position and depresses the' blank into engagement withthe brushes.

This action together with the forward movement of the blanks and the rapid whirling action of the brushes cleans the bottom marginal surfaces of the blank in the same way as the upper marginal edges4 were cleaned at the station A. After passing through both of the stages of cleaning at the station B, the blank is in condition for a subsequent soldering, welding o'r similar operation which, however, forms no part of the present invention.

At the discharge end'of the conveyor .the blanks are piled up in stack form within a magazine. As the conveyor chains take over the sprockets 25 a freshly cleaned blank carried thereon rides oifv of the chains and falls into an inclined chute 2|5 (Figs. 1 and 2) which constitutes the magazine. This chute is mounted on an inclined base 2|6 formed onthe bracket 35.

As a blank slides down into the chute it is set up onedge by a blast of air directed against its under or sliding surface. This is effected by actuation of an ordinary push valve 2|8 of suitable construction which is connected in a pipe line 2|9 having one end threadedly engaged in a bore 22| extending through a boss 222 formed in the bottom of the base 2|6. The bore 22| aligns with an aperture 223 cut through thebottom of the chute. The other end of the pipe is secured,

in a clamp 225 formed in the bracket and may be connected to one end of a flexible hose 226 leading from a suitablesource of compressed air.

The stem of the valve 2|8 is provided with a spring held button 228 which is struck by the high part of an edge cam 229 mounted on the constantly rotating conveyor drive shaft 33. The cam periodically depresses the valve stem and momentarily opens the valve and this is done in time with the travel of the conveyor and hence with the discharge of blanks into the chute.

As a blank slides down the chute the valve is opened'as it moves past the aperture 223 and a blast of air is directed against the blank from the bottom side and adjacent its upper edge. This causes the blank to be set up on edge as shown in Fig. 1. The momentum of the sliding blank is suiiicient to carry it the remainder of the way down the chute in this set up position or until it strikes the blanks already stacked and held against holding flanges 23| formed at the bottom `end of the chute.

The electric motors associated with the machine are preferably of the three phase type and are connected by a three phase system of wiring to a suitable source of electric energy such as a generator 30|, as schematically shown in the wiring diagram in Fig. 7. The generator is provided withservice wires 302 ,-303, 304 which transmit the current through a three phase service switch 305 to lead wires 3| I, 3|2, 3|3. One end of these latter wires are connected to the motor 45 which drives the moving parts of ,the machine proper.

The reversible motors 81, |13 which actuate the blank cleaning brushes 55, |4| are connected into leadxwires 3|5, 3|6, 3|1 which in turn are connected toone set of terminals of a pair of three phase, solenoid actuated, reversing switches 3|8, 3|9. The opposite set of terminals of these switches are connected by wires 32|, 322, 323 to the wires 3| 3|2, 3|3 by means of which electric energy is supplied to the motors. It is the alternate closing of the switches 3|8 or 3|9 which reverses the direction of rotation of the motor shafts to change the direction of. rotation of the l325, 326 which are respectively associated with the switches. One terminal of the solenoid 325 is connected by a wire 321 to the wire 3|3. The other terminal is connected by a wire 328 to one side of a two way switch 329 having a movable element 330. The switch 329 is located. in a switch box 33| which is conveniently secured to the side of the frame I5 (see also Figs. 1 and 2). The movable element is connected by a wire 332 to the wire 3||.

One side of the solenoid 326, which is associated with the switch 3|8, is connected by a wire 333 to the Wire 3|3. The other side of the solenoid is connected by a wire 334 to the opposite side of the two way switch 329. Thus when the movable element 330 of the two way switch is in contact with the terminal end of the wire 328 the solenoid 325 is energized and the switch 3|8 is thereby closed sending electric energy through the motors in one direction. Similarly when the element 330 is moved into contact with the terminal end of the wire 334 the solenoid 325 is deenergized and the solenoid 326 is energized thus opening the switch 3|8 and closing the switch 3|9 so as to send `electric energy through the motors in a reverse direction thus reversing their rotation.

The switch element 330 is moved at intervals when a predetermined number of blanks have been cleaned. This is effected by any suitable means mechanically actuated in time with the passage of blanks on the conveyor chains. A preferred form of device comprises a ratchet arm counter 340 of any suitable construction which may be housed in the switch box 33|. An arm 34| extending into engagement with the leg |0| of one of the bell cranks 93 may/ constitute the ratchet arm to actuate the counter.

Movement of the crank leg when lifting a blank into engagement with the brushes 55 will thus function as the actuator for moving the counter arm 34|. 'I'he counter may be set so as to shift the movable switch element 330 after any predetermined number of blanks have been cleaned and thus reverse the motors. As there are any number of suitable commercial types of counters which can be used successfully, further and more detailed description is thought unnecessary.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the t invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

yI claim: l

1. A machine for cleaning metallic sheets comprising in combination, means for supporting sheets to be cleaned and for conveying them through the machine, abrading means associated with said supporting means, and instrumentalities for pressing the sheets against said abrading means to clean a surface thereof, said abrading means acting on both ends of the sheet for the width of the latter.

2. A machine for cleaning metallic sheets comprising in combination, means for supporting sheets to be cleaned and for continuously conveying them through the machine, abrading means associated with said' supporting means, and instrumentalities for pressing a marginal edge of a said sheet against said abrading means while being conveyed to clean a surface thereof, said instrumentalities maintaining both ends of said sheet in contact with said abrading means for the full Width of the sheet and for a limited length thereof.

3. A machine for abrading metallic sheets comprising in combination, rotating hard and exible filaments for abrading a sheet surface, instrumentalities for pressing the sheets against the ends of said filaments, and control devices actuated by a sheet when in proper position relative to said abrading elements for rendering said instrumentalities effective.

4. A machine for cleaning metallic sheets comprising in combination, means for supporting the sheets to be cleaned, and a rotating hollow Wire brush element associated with said supporting means and rotating on an axis which is substantially perpendicular to the surface of said sheets for abrading a surface thereof, said hollow brush element having means disposed on opposite sides of the brush filaments for holding the same compactly together, and means for pressing the end portion of the sheet against the ends of the brush wires.

5. A machine for cleaning metallic sheets comprising in combination, an abrading element for cleaning a surface of said sheets, said abrading element consisting of metal filaments disposed in parallei relation to one another and having means for holding the iilaments thereof compactly together, conveyor means for moving said sheets and for presenting them to said abrading element, instrumentalities for moving a surface of said sheets into engagement with the ends of the filaments of said abrading element, means for detecting the presence of a sheet when it is presented to said abrading element and for rendering op'erable said instrumentalities, and means for rotating the abrading element on an axis perpendicular to the sheet.

6. A machine for cleaning metallic sheets comprising in combination, an abrading element for cleaning a surface of said sheets, said abrading element consisting of metal iilaments disposed in parallel relation to one another and having means for holding the laments thereof compactly together, continuously operating conveyor means for moving said sheets past said abrading element, instrumentalities rendered operable by a said sheet during its movement by said conveyor for moving a surface of said sheet into engagement with the ends of the filaments of said abrading element, means for causing actuation of said instrumentalities in timed relation with the movement of said conveyor, and means for rotating the abrading element on an axis perpendicular to the sheet.

7. A machine for abrading metallic sheets comprising in combination a rotary abrading element consisting of hard metallic filaments and means for holding the filaments compactly'together, conveyor means for moving said sheets past said abrading element, devices for continuously rotating said abrading element, and means for reversing the direction of rotation of said abrading element, to compensate for the wear of the same in response to the passage by said conveyor of a predetermined number of sheets past said abrading element.

8. A machine for abrading metallic sheets, comprising in combination a plurality of abrading-elements for cleaning surfaces of said sheets. said abrading elements consisting of hard metallic filaments and means fon holding said ilaxnents compactly together, conveyorl means for moving said sheets past said abrading elements, devices for continuously rotating a said abrading element in a direction relatively opposite to another of said elements, and means for reversing the direction of rotation of said abrading elements in response to the passage by said conveyor of a predetermined number of sheets past said abrading elements to compensate for the wear of the same.

9. A machine for cleaning metallic sheets comprising in combination, rotating abrading elements comprising a plurality of wires and means for holding them compactly together with said wires arranged parallel to their axis of rotation for cleaning a sheet surface, means for conveying the sheets to vpass their marginal edges adjacent said abrading elements, instrumentalities for pressing said marginal edges of the sheets against the ends of the wires of said abrading elements, and control devices for said instrumentalities for preventing engagement between a sheet and said abrading elements while the forward part of a said marginal edge is approaching said elements.

10. A machine for cleaning metallic sheets comprising in combination, conveyor means for moving sheets along a desired path of travel, abrading elements disposed on opposite sides of said path of travel and on the same side of a said sheet, each abrading element consisting of a plurality of wires and means for holding the same compactly together and in parallel relation, and instrumentalities acting in opposite directions for pressing said sheets toward and into engagement with the ends of the wires of said abrading elements for cleaning opposite surfaces of said sheets.

11. A machine for cleaning metallic sheets comprising in combination, abrading elements for cleaning a surface of said sheets, each abrading element consisting of a plurality of Wires and means for holding the same compactly together and with the wire ends facing in the same direction, conveyor means for moving said sheets past said abrading elements, instrumentalities for moving a surface of said sheets into engagement with the ends of the Wires of said abrading elements, a latch member operable by said sheets for unlatching said instrumentalities, and holding means operable in time with the movement of said conveyor for delaying movement of said instrumentalities until after the front edge of said sheet is moved into a definite relation to said abrading elements.

12. In a machine for cleaning metallic sheets, the combination of a plurality of abrading elements disposed above and below a path of travel of said sheets and opposite to limited marginal portions only of said sheets, a magazine for receiving sheets in stack formation, a directing wall leading into said magazine and over which said sheets pass upon entering, conveyor means for moving said sheets along said path of travel and for placing them on said magazine directing wall, and air blast means in said magazine actuated in time with the movement of said sheets and directed through an opening in said Wall for setting up said sheets on edge to arrange them in stack formation with the marginal abraded portions of' said sheets in alignment with each other.

13. In a machine for cleaning metallic sheets, the combination of a plurality of abrading elements disposed above and below a path of travel of. said sheets and opposite to limited marginal portions only of said sheets, a magazine for receiving sheets in stack formation, a directing wall leading into said magazine and over which said sheets pass upon entering the magazine, c onveyor means for moving said sheets along said path of travel and between said abrading elements and for placing them on said magazine directing wall, air blast means in said magazine and directed through an opening in said wall for setting up said sheets on edge to arrange them in stack formation with the marginal abraded portions of said sheets in alignment with each other, and devices for actuating said air blast means in time with the movement of said sheets into said magazine.

14. A machine for cleaning metallic sheets comprising in combination a plurality of abrading elements disposed above and below a path of travel of said sheets and opposite to limited marginal portions only of said sheets, conveyor means for moving said sheets along said path of travel and between said abrading elements, and movable means associated with said abrading elements for bringing opposite marginal portions only of said sheets into engagement with said abrading elements for cleaning opposite surfaces of said sheets.

CUS'I'IS S. WOOLFORD. 

